A liquid crystal display device capable of switching between viewing angle characteristics of a display screen if necessary, taking advantage of viewing angle characteristics of liquid crystal, is disclosed in patent document 1 (Japanese Laid-Open Patent Application No. 10-153968/1998 (Tokukaihei 10-153968; published on Jun. 9, 1998).
The liquid crystal display device disclosed in the patent document 1 realizes switching between wide viewing angle characteristics and narrow viewing angle characteristics in the following manner. One pixel is divided into two pixel regions, and the same drive voltage is supplied to the two pixel regions to invert grayscale levels at the oblique viewing angle, thereby attaining narrow viewing angle characteristics. Further, different drive voltages are supplied to the two pixel regions to suppress grayscale inversion at the oblique viewing angle, thereby attaining wide viewing angle characteristics.
However, in the liquid crystal display device of the patent document 1, switching between drive voltages is necessary in supplying a drive voltage to the two pixel regions in one pixel. This causes the difficulty of switching between drive voltages using already-existing wiring. When a switch and wiring, for example, for switching between drive voltages are additionally provided to avoid the difficulty, a part of pixel might be covered by the switch and wiring. This results in the problem of decreasing aperture ratios.
In addition, one pixel is made up of two pixel regions, which causes the problem that the realization of display with high definition is difficult in a liquid crystal display device.